Global Patent Index - EP 0317821 A3

EP 0317821 A3 19901010 - HIGH RESOLUTION DIGITAL PHASE-LOCK LOOP CIRCUIT

Title (en)

HIGH RESOLUTION DIGITAL PHASE-LOCK LOOP CIRCUIT

Publication

EP 0317821 A3 19901010 (EN)

Application

EP 88118590 A 19881108

Priority

US 12552387 A 19871125

Abstract (en)

[origin: EP0317821A2] A high resolution digital phase-lock loop circuit is described, which is implemented with an input clock reference frequency which is approximately the same as the output frequency of the phase-lock loop. The output is derived from delaying the input clock a variable number of gate delays ranging from no delay to one period of the input clock. A shift register controls the number of gate delays and a 360 degree phase detector initializes the shift register when the output is delayed by one period of the input clock to provide no delay. Gate delay variations due to integrated circuit process, voltage and temperature are compensated for to provide a relatively constant clock phase correction.

IPC 1-7

H04L 7/02

IPC 8 full level

H03L 7/081 (2006.01); H04L 7/033 (2006.01)

CPC (source: EP US)

H03L 7/0814 (2013.01 - EP US); H03L 7/0816 (2013.01 - EP US); H04L 7/0337 (2013.01 - EP US)

Citation (search report)

  • [A] EP 0240232 A2 19871007 - HEWLETT PACKARD CO [US]
  • [A] US 3509471 A 19700428 - PUENTE JOHN G
  • [A] EP 0187504 A2 19860716 - LOCKHEED ELECTRONICS CO [US]
  • [A] EP 0157701 A2 19851009 - FUJITSU LTD [JP]
  • [A] IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS, COMMUNICATIONS-SOUND TO LIGHT, Seattle, Washington, 7th - 10th June 1987, vol. 1, paper 18.2, pages 596-600, IEEE, New York, US; M. FUKUDA et al.: "An echo canceller LSI for ISDN subscriber loop transmission"
  • [A] INTERNATIONAL SWITCHING SYMPOSIUM, "Innovations in switching technology", Phoenix, Arizona, 15th - 20th March 1987, paper C7.2, pages 571-576, IEEE, New York, US; R. DIERCKX et al.: "ITT VLSI chip set for ISDN"

Designated contracting state (EPC)

AT BE CH DE ES FR GB GR IT LI NL SE

DOCDB simple family (publication)

EP 0317821 A2 19890531; EP 0317821 A3 19901010; NO 173719 B 19931011; NO 173719 C 19940119; NO 885280 D0 19881125; NO 885280 L 19890526; US 4847870 A 19890711

DOCDB simple family (application)

EP 88118590 A 19881108; NO 885280 A 19881125; US 12552387 A 19871125